An alert which closed part of Birmingham’s main railway station on Saturday afternoon was thought to have been caused by nine police officers suffering from food poisoning.

An area of New Street Station was cordoned off and ambulance staff wearing chemical protection suits rushed to the scene just after 5pm.

The ambulance service said nine people had diarrhoea and were vomiting and three of them were taken to hospital.

Police said the officers fell ill after dispersing a protest march in the city. British Transport Police defended disruption that was caused to travellers, and said the decisions were made on safety grounds.

A West Midlands Ambulance Service spokesman said: “Nine people had diarrhoea and were vomiting. All nine were assessed at the scene. Three were taken to City Hospital for further assessment and treatment. The remaining six were discharged at the scene.”